transit in seoul

90 minutes or so by bus. Yes, you could do it, and spend 4~5 hours hanging out in town, and have to pay the airport tax when you get back in. If you don't want to mess with that, the airport is HUGE- just bring a book, have a snack and a few beers and time will pass!

What's this airport tax? I have never paid it, despite numerous trips to & from Seoul. (I'm an Aussie btw, if that makes any difference.)

When you go back through customs, you have to buy a little ticket, which you have to hand to the folks at immigration before you head in to the departure area. Read up on it here If it is included in the ticket fare, that is peachy. A lot of places do that now, but it becomes null & void once you pass through customs and want to re-enter the airport. 8 hours outside the Bangkok airport cost me $25 in July...The travel agents are not always aware of this, either!

Must be included in the ticket price, or residents in Korea are exempt? Bangkok is in Thailand.

You can get limousine bus to Seoul. It is cheap price but it takes maybe one hour and half.

I can't remember if it was platform 5B or 5A, but they had the cheapest busses to Seoul for 8,500 won. Other busses were 13,500 won. It can take 2 hours o/w, if the traffic / weather is bad. And one hour if good.

I'm sure the airport tax is now included in the ticket price. You had to buy them separately before but not anymore.